Emerging dangers: Deadly effects of an emergent parasite in a new pollinator host.

Highlights: [•] We investigate the status of the emergent honeybee parasite, Nosema ceranae, in bumblebees. [•] We molecularly identify the presence of N. ceranae in multiple species of wild bumblebee across sites in England. [•] We inoculate Bombus terrestris bumblebees with N. ceranae spores to test its infectivity. [•] We find, following the ingestion of N. ceranae spores, bumblebees suffer from altered behaviour and reduced survival. [•] Comparatively, N. ceranae has higher virulence in bumblebees than in its natural honey bee host. [ABSTRACT FROM AUTHOR]